1. Field of the Invention
The present invention relates to an air conditioner of a separate type having indoor and outdoor units, and more particularly, to an improvement of the indoor unit of the air conditioner.
2. Description of the Related Art
Many indoor units of separate-type air conditioners are mounted near ceiling portions of indoor wall surfaces. In general, these indoor units comprise a case assembly formed of front and rear cases, an indoor heat exchanger therein, and a cross-flow fan located behind the exchanger in the case assembly.
In the indoor unit, the cross-flow fan is rotated to suck in air from a room through a suction aperture in the front face of the front case. The suction air passes through the indoor heat exchanger, thereby exchanging heat with a working fluid which circulates in the exchanger. After being regulated in temperature by the heat exchange, the air is blown off into the room through a blow-off aperture in the lower portion of the front case.
Due to the recent housing situation, there is an urgent demand for compact indoor units with reduced height. To meet this demand, some indoor units are designed so that the indoor heat exchanger is inclined backward at a predetermined angle with respect to the vertical line. In these indoor units, the front side of the heat exchanger faces diagonally upward. In some cases, therefore, the suction aperture is located at the top portion of the front case which faces the ceiling of the room.
However, dust easily collects in the suction aperture situated in this position, and often enters the case assembly and adheres to the heat exchanger. If the unit is left in this state for a long period of time, especially during the off-season, the cooling or heating performance of the air conditioner will have been lowered before the restart of use.